Mitigating the risk of Zika virus contamination of raw materials and cell lines in the manufacture of biologicals.

Ensuring the virological safety of biologicals is challenging due to the risk of viral contamination of raw materials and cell banks, and exposure during in-process handling to known and/or emerging viral pathogens. Viruses may contaminate raw materials and biologicals intended for human or veterinary use and remain undetected until appropriate testing measures are employed. The outbreak and expansive spread of the mosquito-borne flavivirus Zika virus (ZIKV) poses challenges to screening human- and animal -derived products used in the manufacture of biologicals.

Multiplex PCR for species-level identification of Bacillus anthracis and detection of pXO1, pXO2, and related plasmids.

The Bacillus anthracis virulence plasmids pXO1 and pXO2 have critical implications for biosafety and select agent status. The proper identification and characterization of B. anthracis and its plasmid profile is important to the biodefense research community.

Arginine-dependent acid-resistance pathway in Shigella boydii.

Ability to survive the low pH of the human stomach is considered be an important virulent determinant. It was suggested that the unique acid tolerance of Shigella boydii 18 CDPH, the strain implicated in a 1998 outbreak, may have played an important role in surviving the acidic food (bean salad). The strain was capable of inducing arginine-dependent acid-resistance (ADAR) pathway.

Reclassification of the Listeria-CAMP test strain ATCC 49444 Staphylococcus aureus as Staphylococcus pseudintermedius.

ATCC 49444, originally designated as Staphylococcus aureus, has been cited as a component strain in the CAMP test for identification of Listeria monocytogenes. A polyphasic study, in which molecular data were combined with cytochemical properties and physiological characteristics, identified this isolate as Staphylococcus pseudintermedius. The nucleotide sequences of the 16S rRNA and sodA genes from ATCC 49444 were determined and found to be identical to those of other S.

Size-based separations as an important discriminator in development of proximity ligation assays for protein or organism detection.

Proximity ligation is a powerful technique to measure minute concentrations of target protein with high specificity, and it has been demonstrated to be effective on a wide variety of protein targets. The proximity ligation assay (PLA) technique is shown to be compromised by the amplification of a nonspecific fluorescent product that is not indicative of protein presence, which was previously unidentified in a published procedure. This result illuminates the complexity of designing the optimal PLA and the possibility of using a size-based separation to increase the reliability of PLAs in general.

Mammalian cell expression of an active site mutant of Pseudomonas exotoxin disrupts LRP1 maturation.

Low density lipoprotein receptor-related protein 1, (LRP1) is a large multifunctional receptor that binds more than 25 physiologic ligands. In addition, it functions as the surface receptor for several Rhinoviruses, HIV-tat and Pseudomonas exotoxin (PE). We report that the expression of PE within mammalian cells can serve as a probe of LRP1 maturation and functionality.

Bacterial toxins as tools for mucosal vaccination.

Several studies have demonstrated that the biological properties of secreted bacterial toxins could be harnessed for the induction of mucosal and systemic immunity following application at epithelial surfaces. Although the properties and potential application of several of these toxins will be discussed in this review, special focus will be placed on Pseudomonas aeruginosa exotoxin A (PE). A non-toxic form of PE (ntPE) into which antigenic epitopes can be integrated appears to be a particularly promising vaccination tool, which is able to cross the polarized epithelia of the gastrointestinal, respiratory and reproductive tracts and selectively target macrophages and dendritic cells.